White House: Islamic State Has 'Gained Capacity' In Recent Months

Deputy National Security Adviser Ben Rhodes says the beheading of an American journalist by Islamic State militants this week is tantamount to a terrorist attack on the United States and that it comes as the al-Qaida-inspired extremist group has "gained capacity in the last several months."

In response to a question from a reporter at an afternoon briefing, Rhodes said the U.S. sees the killing of journalist James Foley "as an attack on America," adding that Washington is "moving heaven and earth to find and bring home American hostages" held captive in the region.

"We will be relentless in protecting Americans," he said.

The comments from Rhodes largely echoed remarks earlier in the day by Pentagon spokesman Rear Adm. John Kirby, and strong words about the group known variously as Islamic State, ISIS or ISIL made Thursday by Defense Secretary Chuck Hagel and Chairman of the Joint Chiefs of Staff Gen. Martin Dempsey. Hagel said the Islamic State extremists go "beyond anything we've seen."

However, Kirby said U.S. airstrikes had "succeeded in blunting [Islamic State] momentum."

Asked whether the U.S. planned to expand its air campaign against the group in northern Iraq, possibly into Syria, where it has also been active, the admiral replied: "We don't telegraph our punches, but I think you can rest assured that the leadership team here in the Pentagon understands the threat."

Kirby defended a failed operation to rescue Foley and other hostages in Syria. He said that although U.S. forces participating in the rescue effort found no hostages at the target location, "we had an indication that they were once on that site.

"Attempts like this — which was risky under the best of circumstances — they take time," he said. "Intelligence is not perfect."